Cement



PM Realm UNITED STATES PATENT OFFICE CEMENT ma.my,n.r.,mmu

llalowax Corporation. New York, N11, a corporation Delaware No Drawing. Application March 6, 1929 Serlal'No.. 344,926

2 Claims. (0]. 87-17) This invention relates to that class of cements which depend upon fusion and subsequent solidification to obtain adhesion and comprises compositions having high tensile strength and high 5 melting points and capable of securing glass to glass or metals, woodto wood, etc.

The compositions corresponding to this inven-,

tion have for their basis a wax-like halogenated naphthalene which in itself is brittle and devoid of adhesiveproperties. I have discovered, however, that if there be incorporated with such a product natural resins or gums or products derived i'rom such natural resins or gums, which in themselves are in general not suitable as eements, that compositions with good adhesive P operties are obtained. Among the natural resins or gums found suitable for this purpose are rosin, shellac, ccpal, latex, rubber, etc., .and among their derivatives are ester gums, etc.

Plasticizing agents, such as castor oil, etc., can

also be included.

A cement in accordance with this invention can be obtained by dissolving ester gum, that is rosin neutralized with glycerin, in a molten chlorinated naphthalene comprising mainly a trior a tetra-chloro-naphthalene. These are mixed in substantially equal parts by weightthough the pr p rtions :may be varied consid v-therefrom,preierablynotlessthanthirtyper so cent of chlorinated naphthalene, and still yield a satisfactory cement. Such a cement is applied by heating the articles to be united substantially to or above the fusing point of the cement, that is about 110 C., coating the surfaces with the as fused cement and then maintaining thesurlaces in close contact until the cement solidifies. Pieces molded from a composition 01 a phenolic resinoid and a wood flour filler have been bonded inthismannerwithacementmaderromequal '40 partsoi'estergumandchlorinatednaphthalene;

and when tested, the bondhas shown a tensile strength of about 700 pounds to the square inch.

Comparative tests show that a well-known sealing wax or shellac composition has a tensile strength or about 450 pounds-to the square inch 80 and a rubber cement about 130 pounds to the square inch. A small addition of rubber latex, that is about five per cent, gives linprovedtensile strength, tests indicating. a strength of about 900 pounds to the square inch. The latex is incorporated in the mixture of chlorinated naphthalene and ester gum while the mixture is in a fused condition.

Substantially equivalent results are obtained 7 when copal, resin, etc., are substituted for the ester gum. For example, about '10 parts by weight of copal are added to about 30 parts of a chlorinated naphthalene containing principally trior tetra-chloro-naphthalene. Aplasticizer or softening agent is preferably includeddor instance. about 10 per cent of castor oil. Such a cement has a melting point-o1 about 110 C. and

a tensile strength of about 750 pounds per square Manon a. 

